Knight is the latest in a series of suitors for USA Truck, which has struggled to turn a profit dating back to 2008. Activist shareholder Liberate Technologies made a $240 million unsolicited bid in 2006, and trucker Celadon Group (CGI) in 2011 announced a 6.3% stake ahead of a potential offer.
Celadon sold its shares in March 2012, though analyst Fowler noted that USA Truck has overhauled parts of its board and management since.
Knight is being advised by Evercore Partners (EVR) and Fried, Frank, Harris, Shriver & Jacobson.
Written by Lou Whiteman